Disposable hypodermic syringe



Nov. 4, 1952 J. w. HART DIsPosABLE HYPODERMIC SYRINGE Filed Nov. l, 1951Pieri 8 JNVENTOR.

f@ Armen/Ev JOHN W. HART BY MM Ear@ Patented Nov. 4, 1952 2,616,420DISPOSABI'IE HYPODERMIC SYRVING .lohn W. Hart,` Albany, N. Y.,v assignorto Sterling' Drug Inc., New York, N. Y, a corporation of DelawareApplication November 1, 1951, serial No. '254,410

2 Claims.

This invention relates to new and improved disposable hypodermicsyringes and the principal object of the present invention is to providesuch a syringe which is small, simple in construction and use, and whichis inexpensive to manufacture so that it may be used and disposed of,preferably after a single use, and an exact quantity of content may beinjected in the patient or expressed for testing purposes, etc.

Another object of the invention resides in the provision of such asyringe comprising an ampoule preferably made of plastic or otherconvenient material and itself providing the syringe barrel and otherparts as will become more apparent hereinafter, said ampoule having anopen end closed by a plunger and a closed end forming a diaphragm, therebeing an open-ended tube extending outwardly from the diaphragm andreceiving a double-ended needle, and guide means for the needle engagingthe inner wall of the tube, in combination with a needle guard itself inthe `form of a tube having an open end which enters the first-named tubeand completely encloses the needle for storage, transmissiometc., saidneedle guard being easily and quickly depressed by means of the fingerof the operator to engage the needle guide and move the same and theneedle to cause the distal end of the latter to penetrate and pierce thediaphragm so that the device is set to inject or express the contentthereof upon removal of the needle guard.

A further object of the invention resides in the provision of thedisposable syringe in which the needle guard is provided with meansadjacent the open end thereof for engagement with the plunger so thatthe needle guard, being removed from the ampoule tube after causing theneedle to pierce the diaphragm, may be engaged with said plunger foraspirating or injection in the usual manner of a syringe.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings in which Fig. 1 is aview in elevation showing the device in storage condition, part beingbroken away;

Fig. 2 is a vertical section through the device of Fig. 1;

Fig. 3 is a view similar to Fig. 1 but showing the needle guard in theact of causing the needle to pierce the diaphragm;

Fig. 4 is a view similar to Fig. 3 but showing the needle guard removedfrom the syringe;

Fig. 5 illustrates the needle guard secured to the plunger and inposition for use of the syringe;

Fig. 6 is a sectional view on an enlarged scale through the ampoule tubeand needle guard and showing the parts in position prior to actuation ofthe latter;

Fig. 7 is a similar View but shows the needle guard having caused thepiercing of the diaphragm; and

Fig. 8 is a section on an enlarged scale through the plungerillustrating the needle guard secured thereto and actuating the same.

As shown in Figs. 1 and 2, there is provided an ampoule generallyindicated at I0 and having an open end at I2, a reduced neck I4, and anintegral outwardly extending open-ended tube I6. Between this tube andthe reduced neck I4 there is a diaphragm I8 which effectively closesthis end of the ampoule. It is seen that this ampoule is made in onepiece and it is preferably of a molded plastic material such aspolyethylene or similar material that is easily molded and slightlyflexible and springy so that a good sliding friction iit may beoccasioned by a rubber plunger as shown at 20 without the danger ofleakage under ordinary conditions.

Hence, although the plunger is movable within the body of the ampoule,it nevertheless effectively closes the same and prevents any accidentalescape of ampoule content under usual conditions. At the same time thediaphragm I8 may be readily pierced by a needle but it is notfracturable and when pierced by a needle will tend to hold the same inposition due to the resilience of the material itself.

The tube I6 receives a needle guide 22 with a sliding frictional t. Theneedle guide 22 is preferably metal and centrally secured to it is theneedle itself indicated at 24. This needle has an end at 26 which issharpened suiiiciently to penetrate and pierce the diaphragm I8 and ofcourse the opposite end at 28 performs the injection. The needle guide22 holds the needle in the positions shown in Figs. 1, 2, and 6 at alltimes when the device is not in use, i. e. during storage,transportation, etc. The needle guide 22 may be pushed within the tubeI6 from the Fig. 6 position to that of Fig. 7 wherein it is seen thatthe inner end of the needle has pierced the diaphragm so thatcommunication is made between the needle and the interior of theampoule.

A hollow tubular needle guard 30 is provided and this element may have alight frictional sliding t in the tube I6. There is little resistance tosliding of the needle guard 30 in tube I6 but there is sufficientresistance to normally maintain these parts in the relative positionsshown in Figs. 1 and 2. The needle guard 30 is closed by an enlarged end32 which acts as a button or means by which the same may be engaged bythe operators lingers, see Fig. 3, for the purpose of pushing needleguide 22 together with its needle downwardly to cause the needle topierce the diaphragm. This is accomplished by the inner end of theneedle guard 30 as at 34 engaging the top of the needle guide 22 asshown most clearly in Fig. 7. This puncturing or piercing action isordinarily achieved by holding the device between the thumb and forengerand exerting a light compressive pressure thereon as will be clear. Theneedle guard clearly and completely encloses and protects the needle aslong as the guard is in place as so far described.

The needle guard 30 is provided with some means such as external threads35 which are formed integrally therewith, for engagement with internalthreads 38 in the plunger 20. Any other positive connection would causethe same result, i. e. connecting the open end of the needle guard 30with the plunger whereby the latter may be moved in either direction foraspiration or injection, and the device is held, manipulated, andoperated just about as is the usual syringe.

It will be seen that this invention provides a relatively simpledisposable and preferably single use syringe which takes little spaceand which needs no other parts to operate it. It need not be opened asthis is accomplished by the needle itself in piercing the diaphragm i8;it requires no external syringe parts at all; it is cheaply and easilymade, and very easily stored, prepared for use, and handled in general.The needle is kept covered and sanitary at all times when not in use,and the needle guard itself has a dual function as clearly explainedabove.

Having thus described my invention and the advantages thereof, I do notwish to be limited to the details herein disclosed otherwise than as setforth in the claims, but what I claim is:

1. A disposable hypodermic syringe comprising a plastic one-pieceampoule having an open end, a closed end in the nature of a diaphragm,and a tube extending outwardly from the diaphragm and terminating in anopen end, a plunger closing the open end of the ampoule, a double endedneedle, a needle guide for the needle, said needle guide having asliding frictional fit in the tube with the distal end of the needlefree of the diaphragm but adjacent thereto, a needle guard slidablyarranged with respect to the tube and completely closing the same, saidneedle guard being slidable manually to engage the needle guide and movethe needle to pierce the diaphragm, said needle guard being removablefrom 'the tube and engageable with the plunger to actuate the same toexpress the content of the ampoule through the needle.

2. A disposable hypodermic syringe comprising a plastic one-pieceampoule having an open end, a closed end in the nature of a diaphragm,and a tube extending outwardly from the diaphragm and terminating in anopen end, a plunger closing the open end of the ampoule, a doublepointed needle, a needle guide for the needle, said needle guide havinga sliding frictional t in the tube with the distal end of the needlefree of the diaphragm but adjacent thereto, a needle guard slidablyarranged with respect to the tube and completely closing the same and anenlarged head on the needle guard for digital engagement and consequentmotion to cause the needle guard to engage and slide the needle guideconsequently to cause the needle to pierce the dia phragm, said enlargedhead being capable of being grasped to retract the needle guard andremove the same from the tube, and means on the needle guard to engagethe plunger, said enlarged head then being digitally engageable to tocause motion of the plunger.

JOHN W. HART.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS Number Name Date Re. 19,219 Smith June 19, 19341,687,502 Marey Oct. 16, 1928 2,550,394 Young et al Apr. 24, 1951

